As the first driver (wouldn't say owner, parents car), I have a 2004 M3 with 120,000km along with Extended Warranty up to 140,000km. I might extend it again up to 160,000km. I've paid $8000 for Ex Warranty but had $12,000 worth of parts and labor claimed.

Problems up until now covered under warranty.
1. 2 Cats failed at 75,000km.
2. Alternator failed at 70,000km.
3. AC failed 3 times in span of 1.5 year. It's currently at the dealership getting fixed under warranty. They finally found the leak after 2 tries.
4. Pedal shifts weren't working at around 85,000km.
5. Driver Window switch didn't work at 85,000km.
6. LSD Left Seal leaked twice every two years.
7. SMG was reprogrammed at roughly 45,000km. It had 2 seconds delay between gears. This happened when I put my Iforged 19's on. I guess the ECU couldn't adjust to aftermarket wheels very well. However, the reprogram helped. No more issues with my SMG (knock on wood). I've had 3 different sets of rims after Iforged Rims. Still no issues.

Things I will do in the future:
1. When ICBC Aircare goes out of business, I will install straight pipes if my cats fail on me again. I am not going to pay $6000 on two cats. Apparently, they're $3000 each. That's what I've been told by my service advisor.

2. Change my stock suspension to coilovers at 140,000km.

3. Prepare a budget to change LSD Seal, which was roughly $650-700 when it was fixed by BMW dealership under warranty if I remember correctly.

4. Prepare a budget to change the hydraulic pump. I haven't changed mine yet, but I already prepared $2500 in case something happens. This is NOT COVERED by warranty. It is a wear and tear part.

Engine wise, still running strong! Dynoed it in March, I was able to get 3250hp/230tq. Number decreased. what can you expect. it's 7.5 yrs old. haha

Oil change at every 12,000km with Lubro 10W60. Last longer and cheaper.

I've never used the launch control.

End of the story, it's best if you get an aftermarket extended warranty for a E46 M3. If not, prepare to pay some big bucks.

Oh, I meant to ask you about this BC Clean air thing, why couldnt you just buy some race Cats or even a by pass pipe if your in Van?? Before I sold the JCW it had to be safetied and stuff to get the out of Provence test passed, so I could re-register it! Then we did the same with my Mrs 2006 R50 Mini and that was the same no problems, but now im concerned that their is an annual test or something that prevents just doing what you want exhaust wise?!?!!? Am I reading this right? If I got an M3 and it needed exhausts or Cats replacing I would never go main dealer (though I understand why you did), I would just get a stainless made or something, or source a part from a wreckers..........